Numerous types and variations of dynamoelectric machines, such as motors, and generators, have been constructed. Each have included a stator portion and a rotor portion. The rotor portion, which is usually an armature, although it may also be a rotating field assembly, is provided with a contact surface such as a commutator or slip ring, and with brushes or the like for establishing electrical contact with the rotor. Brushes have been maintained in proper orientation in numerous different manners, and interconnections between brush leads and stator leads, in the case of wound stators, have been connected in numerous ways. In addition, motors have been made waterproof or water resistant, such as for use in submersible or marine applications in numerous ways. Also, terminal leads for conveying electrical energy to or from the machine have been connected to the machine in various ways. Connections between stator windings and brushes are conventionally made by stripping the wire or lead ends and splicing them together, although screw-and-nut interconnections have been also provided. Further, brush holding structures have been made in a fashion suitable for plugging into a terminal board terminating wiring from stator windings, for interconnecting stator windings and rotor windings, through the brushes. As will be apparent, such structures are expensive to produce, time-consuming to assemble, difficult to align, and inconvenient to service or repair.
Such dynamoelectric machines have been made waterproof or water resistant by providing a terminal box on the exterior of the machine, the box having a waterproof cover and an opening adapted to receive a sealing grommet or the like. After an appropriate electricl cable was passed through the sealing grommet, or itself provided with an appropriate sealing grommet, the wire ends were connected to those extending from the dynamoelectric machine into the connection box with splices, or with individually insulated nut and bolt connections. Also, external cables have been directly wired to stator windings and to brushes, and passed through a sealing grommet or the like in the housing of the dynamoelectric machine. As will be apparent, such a sealing grommet is not easily repositionable to adapt the dynamoelectric machine for different purposes or tasks.
Brush holding structures have been constructed in various ways, and typically include, at least in the case of smaller dynamoelectric machines, some type of mounting plate through which the rotor shaft passes, made of an insulating material, and brush guide tubes or slots, sometimes called brush boxes, made of conductive metal. The conductive metal is typically used for its temperature-resistant characteristics, rather than for its conductive characteristics, since the cumulative effect of the small energy loss between a brush and its contact surface causes considerable heating of the brush. It has also been proposed to mold a brush holder structure from a plastic material of the type which has a high temperature-withstanding capability. However, molding compounds for such use are considerably more brittle than molding compound for making items of a lower temperature-withstanding ability, requiring thick structures for strength. Also, materials with comparatively high strength and flexibility lack high-temperature withstanding ability.
The instant invention overcomes these and other deficiencies of the prior art.